(a) Field of the Invention
The present invention relates to tobacco feeding apparatus and more particularly to tobacco feeding apparatus which selectively meters the amount of tobacco being fed thereby.
(b) Description of the Prior Art
Various tobacco feeding apparatus are known to the art.
U.S. Pat. No. 1,808,794 teaches a tobacco spreader device including a moving sieve band subjected to a suction action and functioning to form a tobacco fleece, an impervious moving feed band located next to the delivery point of the sieve band such that the moving impervious feed band interrupts the suction action adjacent the delivery point of the sieve band and carries the tobacco fleece out of the range of the suction action exerted on the sieve band.
U.S. Pat. No. 3,030,966 teaches an apparatus for forming a continuous tobacco filler to a cigarette making machine. The apparatus includes an air-pervious conveyor with a device to feed the tobacco upwardly to the conveyor. A suction device is located above the conveyor to cause air flow upwardly through the conveyor whereby tobacco on the conveyor is held on the underside of the conveyor forming a tobacco filler. A trimmer having rotating trimmer discs which is located downstream of the air-flow zone trims the tobacco filler to a desired cross-sectional size by removing surplus tobacco from the conveyor. A hopper is located beneath the trimming device to receive the surplus tobacco.
U.S. Pat. No. 3,088,468 teaches an apparatus for use with a cigarette making machine for forming a tobacco filler which includes an air pervious conveyor to convey a stream of tobacco from which the filler is to be formed by the removal of excess tobacco. The conveyor has opposed side walls having tobacco engaging surfaces defining a tobacco confining channel, and a suction device to draw air into the channel and through the conveyor so as to flow through and compress the tobacco confined in the channels. A trimming device is located over the conveyor to separate and remove tobacco therefrom to form a filler of desired depth.
U.S. Pat. No. 3,095,883 teaches a continuous rod cigarette making machine in which a continuous tobacco filler is formed on an air-pervious conveyor, and is held to the conveyor by suction.
U.S. Pat. No. 3,111,026 teaches a continuous rod cigarette making machine in which a continuous tobacco filler is formed including an endless air pervious conveyor with a suction chamber in communication with the top run of the conveyor to draw air through the top run to hold the tobacco filler to the conveyor.
U.S. Pat. No. 4,207,907 teaches a cigarette making machine which includes an air-pervious band which carries a cigarette tobacco filler by means of suction to a cigarette wrapper web.
U.S. Pat. No. 4,564,027 teaches an apparatus for building a continuous tobacco stream at one side of an air permeable conveyor, the other side of which is adjacent to a suction chamber. Two side walls which define with one side of the conveyor a tobacco channel receiving tobacco particles merge and is provided with inclined passages for the flow of compressed air in directions having components in the direction of travel of the tobacco stream. This ensures that all of the tobacco particles are accelerated in the direction of travel of the stream before they enter the channel on their way toward the one side of the air permeable conveyor.
U.S. Pat. No. 4,610,260 teaches a distributor of a cigarette making machine having an air permeable tobacco transporting conveyor adjacent to a channel which is bounded by two sidewalls and receives a mixture of tobacco particles and compressed air. The quantity of air entering the channel exceeds the quantity which can be evacuated through the air permeable conveyor. Therefore, at least one of the sidewalls has a recessed air-permeable portion adjacent the external suction chamber to draw surplus air from the channel without adversely influencing the trajectories of tobacco particles which are propelled toward the conveyor to form thereon a growing homogenous tobacco stream.